Chain saw machine



Feb. 27, 1945. A. w. MALL CHAIN SAW MACHINE Filed April 24, 1942 4Sheets-Sheet 1 //v VEN rofl BY ATToR/VEY Feb. 27, 1945. A w MALL2,370,556

CHAIN SAW MACHINE Filed April 24, 1942 4 sheets-sheet 2 /NVENTDR Feb.27, 1945.

A. W. MALL CHAIN SAW MACHINE Filed April Fia.

24, 1942 4 Sheets-Sheet 3 Feb. 27, 1945. A. w. MALL 2,370,555

CHAIN SAW MACHINE Filed April 24, 1942 4 Sheets-Sheet 4 92 819s 7g 5Pf6/2, 7574 sl sa /A/ VE'IY TOR @Mia/zzz.

Patented Feb. 27, 1945 UNITED STATES PATENT oFFicE cnam saw ArthurWilliam Mall, Flossmoor, lll. Application April 24. 1942, serai No.440,303

l (ci. 14s-sz lOlalm.

My invention relates to chain saw machines and has as its primary objectthe provision of an auxiliary engine for supplying added power to thecutting chain. By employing two engines to drive the cutting chain,I amable to maintain a minimum diameter for the driving sprockets and inturn a minimum width for the chain guide plate.

Another object of my invention is to provide a iloating" chain guideplate! A further object is to provide improved means for adjusting theguide plate rotatively relative to the engines and for detaching theengines from the guide plate.

A further object of my invention is to provide The engines A and B maybe identical in mechanical construction so as to have interchangeabilityof parts and they are of the same size and capacity so that eachoperator carries the same an improved engine cooling device and enginestarting device.

Other objects and advantages of my invention v will become apparent uponreading the following specification and upon examination of the drawingsin which:

Fig. 1 is a side elevational view of my improved chain sawing machine;

Fig. 2 is a fragmentary sectional view of the adjusting device foradjusting the guide plate rotatively relative to the engines and fordetaching the engines from the guide plate;

Fig. 3 is a fragmentary sectional view of one end of the chain sawmachine showing the guide plate in a horizontal plane:

Fig. 4 is a fragmentary front view taken on line 4-4 of Fig. 3;

Fig. 5 is a fragmentary sectional view taken on line 5 5 of Fig. 3;

Fig. 6 is a fragmentary sectional view taken on line 8--8 ofFig. 3;

Fig. 7 is a fragmentary detail viewl of the underneath side of thesprocket supporting casting;

Fig. 8 is a detail front view of the special nut used in connection withthe chain tensioning device;

Fig. 9 is an enlarged fragmentary view of the chain tensioning bo t;

Fig. 10 is a fra engine starting device and cooling system;

Fig. 11 is a sectional view of the oil tank condensed from its normallength;

Fig. 12 is an enlarged detail sectional view of the driving sprocket;and

Fig. 13 is a perspective detail view of the crank holding lever. y

Referring to Fig. 1 I have shown thev preferred embodiment of myinvention which is comprised generally of gasoline engines A and B,chain guide plate C and cutting chain D.

entary sectionalview of the i amount of weight when operating the sawingmachine. Each engine is provided with a centrifugally operated automaticclutch comprised of a driving clutch member 2 secured to the engineshaft 3 of each engine A and B. The drive ing clutch member 2 has clutchshoes 4 pivotally mounted on clutch member 2 so as to establish drivingconneotionwith driven clutch member 5. Driven clutch member 5transmitsrotation to sprocket shaft 6 through the'medium of gear 'I andsprocket I6 drives the cutting chain D. It is to be noted vthat oneengine may be operated without operating the second Aengine if desired.This is accomplished by virtueI of the fact that there is an automaticclutch at each end of the sawing machine.V Thus, if engine B were beingoperated and engine A were idle, the driven clutch member B would berotating (viewing Fig. 3) however, there would be no driving connectionbetween clutch member 6 and clutch shoes I. The only time clutch shoes 4establish driving connection with clutch member E is when engine shaft 3is rotated.

Referring to Fig. 1 it will be noted that the v chain guide plate C isnot shown in its normal ting chain D is applied to the log and the logil'isdes vagainst curved surface il of guide bracket It is to be notedthat when both engines are operating at the same speed, they each impartequal horsepower to the drive sprockets I6 and I1, thereby distributingthe torque load equally on each drive sprocket. .This distribution oftorque load permits the use of a drive sprocket of smaller diameter,thereby, in turn, permitting the use of a chain guide plate D of minimumwidth. The reason for using a guide plate of minimum width is importantwhen felling a standing tree-the less the width of the guideplate--the'sooner a wedge can be driven in the flr'erf ofthe tree toprevent the treefrom pinching the cutting chain.

It can be seen that when the widthof the guide plate is reduced to aminimum. its resistance to handles 2I and 22.

bending is likewise' reduced, consequently when my sawing machinels-cutting in a horizontal plane, guide plate C is caused to bendarcuately. To remedy this I have `provided a pair of straps I9 and 20having their free ends secured to opposite sides of the engines. Theloop portions of the straps may be placed around the operators neck andshoulders to permit the weight of the sawing machine to be carried bythe operators body as well as his hands and arms which graspConsequently, it is easy for the operators to exert a slight downwardpressure on handles 2I and 22 against the leverage obtained throughstraps I9 and 20 thereby oisetting or counterbalancing the gravity loadon guide plate C 'and thereby eliminating any tendency of guide plate Cto bend.

It can be seen that by using two engines of equal weightand size I haveobtained a well balanced sawing machine in which each operator carriesan equal amount of weight when operating the sawing machine and at thesame time I have supplied twice as much power to the cutting chain D. Aspreviously pointed out, the engines A and B are preferably identical inmechanical construction. Likewise, each end of the sawing machine isprovided with lubricating systems of identical construction, enginestarting and engine cooling devices of identical construction andtransmissions (including automatic clutches, sprockets. and gears) ofidentical construction.

Itis to be noted that gear housings 3I are both located on the same sideof guide plate C, whereby when guide plate C is adjusted to a horizontalplane for cutting down a standing tree, then guide plate C can beoperated within 2 or 3 inches of the ground, thereby eliminating treestumps.

Referring to Fig. 3, I have shown the manner in which I provide afloating guide plate. Guide plate C is provided with an elongated slotthrough which bolts 26 extend. Guide bracket 21 is provided with anupwardly extending elongated rectangular shoulder 28 which provides aguide for slot 25 of guide plate C. Guide plate C may be adjustedlongitudinally relative to guide brackets 21 and I 5 by loosening bolts26 and manually moving said guide plate. When bolts 26 are retightened,bracket I 5 clamps the guide plate C in a fixed position. This effects arough adjustment of the tension of cutting chain D.

Referring to Figs. 3, 4, 5, 6 and '1, I have also provided a casting 30which is rigidly secured to gear housing 3|. Casting 30 has a downwardlydepending annular flange 32 received in the upper end of gear housing 3|and serving as a bearing retainer for bearing 33. Casting 30 also has anoutwardly extending shoe 34. Said shoe is provided with a centrallylocated elongated rectangular shoulder 35, which shoulder is arcuatelydished throughout its length at 36 so as to provide a bearing surfacefor spring 31. Guide bracket 21 is provided with a central bore 38 whichreceives compression spring 31. Shoulder guides.

bracket 21 which bracket is formed with an elongated slot 39 so as to beslidable relative to casting 2 and so as to be guided by guide rail 35.It will be noted the bore 38 in bracket 21 has parallel walls 4Il-,and`4I thereby providing a channel having an interior contour correspondingto the exterior contour of nut 42. Nut 42 is,.thereby,' slidable withinbore 38, but is non-rotatable relative thereto. The flat underneathsurface of nut 42 rides on shoulder 35. An adjustment screw 44 lsthreadedly received by nut 42 and has a circular shoulder 45 which isbiased against a semicircular shoulder' 46 on casting 30.y Thesemicircular shoulder 46 is formed by means of a boss 41 which isintegral with casting 30 and which is provided with a slot 49. Screw 44has a stub shaft portion 50 which is received in slot 49 so as to berotatable therein. It can be seen that by rotating screw 44, nut 42 iscaused to move axially of said screw thereby increasing or decreasingthe tension on spring 31 (depending upon the direction of rotation ofscrew 44). 'Screw 44 may be rotated by inserting an Allen wrench throughhole 48 in bracket 21 into the square hole 5I in the outer end of screw44. Screw 44 may also be adjusted by using a crescent wrench on headportion 52. It can be seen that when screw 44 is rotated it cannot moveaxially in the direction of sprocket shaft 6 because of shoulder 45being biased against shoulder 46. Likewise, screw 44 does not moveaxially in a direction away from sprocket shaft 6 because of theresistance of spring 31 abutting against nut 42. 'I'he tension stored inspring 31 is opposed by the tension of cutting chain D which is trainedaround sprocket 8. Therefore it can be seen that the tension of cuttingchain D may be accurately adjusted by rotating screw 44 in eitherdirection. It can also be seen that since each end of the sawing machineis provided with the same type of chain tensioning device as shown inFig. 3, then guide plate C may be considered to iloat between theopposing tensions of springs 31 at each endof the sawing machine.

When cutting chain D is removed from sprocket I 6, there is nothing toresist the outward thrust of compression spring 31, consequently, I haveprovided a pair of parallel slots 56 in the underneath surface of shoe34. Two pairs of bolts 51 and 58 extend through slots 56 `and arethreaded into bracket 21 so as to be movable along with bracket 21. Saidbolts have shoulders 59 which prevent threading them toc far intobracket 21. A pair of flat bars 60 and 6I provide a at bearing surfacefor riding against the underneath surface of shoe 34. When bolts 51 and58 are tightened so as to cause shoulders 59 to be tightened against theunderneath surface of bracket 21, then there is enough play to permitsliding movement of bracket 21 relative to shoe 34 within the limits ofslots 56. Thus when cutting chain D is removed from sprocket I6, spring31 urges bracket 21, guide bracket I5 and guide Plate C outwardly untilbolts 51 and 58 reach the ends of slots 56.

I have Provided an automatic lubrication system for lubricating thecutting chain at all times while the sawing machine is operating..Mounted on each. end of the sawing machine is an oil container 64secured to gear housings 3l by means of strap irons 65. Each oil tank 64has a plunger 66 therein which is continually under tension bycompression spring 61. When relling the oil tank, plunger 66 isretracted by pulling handle 68 outwardly. The oil is then insertedthrough opening 69 and a sealing cap 10 (not shown in Fig. 11) isthreaded into opening 69. A second opening 1I in the oil tank has aconduit 12 (Fig. 3) threaded thereinto which conduit is also threadedinto gear housing 3| thereby directing the oil from tank 64 intocompartment 13 in gear housing 3 I. It can be seen that the oil fromtank 64 is urged into compartment 13 under pressure at all times due tospring 61 acting on plunger 66. The oil travels through oil passage 14in sprocket shaft 6 until it reaches passage 15 (Fig. 12) also in thesprocket shaft. Passage 15 opens into pasoil in passage 16 is preventedsages 18 in sprocket hub 11. The oil then travels through passages 18which open into the sprocket teeth 19. The sprocket teeth constructionmay be of the type shown in the .co-pending application, Serial No.436.014, by myself and Walter L. Gorden. In order to assure that thecutting chain will be lubricated automatically while the saw isoperating, which lubricant supply is cut of! when the saw is notoperating. I have provided a. centrifugally operated valve device whichwill admit lubricant to the sprocket teeth regardless of what positionthe sawing machine may be in.

The valve device is comprised of aplurality of balls 8| preferablyspaced 90 degrees from each other so as to have a total of four. Eachball is radially movable within cylindrical chamber 82. The bottom ofeach chamber 82 is dished to form a valve seat 83 having a contourcorresponding to the spherical contour of balls 8| so that when theballs 8| are seated in said valve seats 83, the from flowing past balls8|. In Fig. 12 I have shown one of the balls 8| in its normal seatedposition and the other ball in unseated position.

When the engine is not running sprocket shaft 8 is idle and compressionsprings 85 urge balls 8| into seated position. Set screws 88 may beadjusted to vary the tension of springs 85. When the engines are startedup, sprocket shaft 8 is rotated, thereby imparting rotation to sprockethub 11. When a predetermined speed of rotation of sprocket hub 11 isreached, centrifugal force causes balls 8| to overcome the resistance ofsprings 85 and said balls move radially outwardly so as to permit theoil in passage 18 to flow through passage 18 into the sprocket teeth.The teeth of cutting chain D are consequently lubricated as they travelaround sprocket teeth 19. In order to prevent sawdust from cloggingpassages 18, I have provided enlarged tapered openings 88 in thesprocket teeth 18 which facilitate disposal of sawdust.

Referring to Figs. 1 and 2, I have provided means for rotativelyadjusting guide plate C and cutting chain D relative to engines A and Bso as to permit sawing in either a horizontal or a vertical planewithout changing the position of the engines A and B from their normalupright positions as shown in Fig. 1. Said rotative adjustment meansalso permits separating the two engines from the guide -plate andcutting chain, whereby to facilitate transporting the sawing machinefrom one locality to another. Gear housing 3| has a circular flangeportion 82 which embraces a circular flange portion 83 on engine casting84. Flange 82 may be provided with a series of four or more openings 85into which steel bushings 88 may be cast. Flange 83 is also providedwith an equal number of openings 81 to register with the openings insteel bushings 86. It is to be noted that the inner periphery of flange82 and the outer periphery of flange 83 are tapered for reasons whichwill be hereinafter described. Formed integrally with engine casting 84are two bosses 88, one located on each side of engine casting 94 so asto Ibe diametrically opposite each other. Said bosses have an interiorsurface 88 which is arcuately concaved (not shown in drawings) so as toconform to the arc defined by the exterior periphery of flange 82. It isto be noted that the outer annular edge of flange 83 abuts againstannular shoulder |0| formed at the base of flange 82. A second annularshoulder |02 is also formed in flange 82. A pin |03 extends through boss88 into the openings in steel bushings 'of a spring pressed ball |04seated in 88 and openings 81 in flange 83. Said pin |03 is normallyanchored in the position shown in Fig. 2 by means annular groove |05 inpin |03.

When it is desired to rotate guide plate C, cutting chain D and gearhousing 3| relative to engine casting 84, pins |03 are manuallyretracted to the positions shown in dotted lines in Fig. 2. Then gearhousing 3| is manually rotated to the desired position of adjustment andpins |03 are pushed back into the openings in anges 82 and 83 to anchorgear housing 3| relative teengine casting 84. The tapered exteriorperiphery of flange 83 and the tapered interior periphery of flange 82facilitate rotative movement of gear housing 3| relative to enginecasting 84.

It is to be noted that when gear housing 3| is rotated to a new positionof adjustment, peripheral edge |00 of flange 93 rides against annularshoulder |0| thereby serving to keep the openings 86 and 91 aligned in acommon radial plane so as to facilitate inserting pin |03 into said openings.

When it is desired to detach gear housing 3| from engine casting 84,this is accomplished by loosening screw |08 which is threaded into theouter end of boss 88. Bar |01 is then manually pulled outwardly withinthe limits of slot |08 and the inner end of bar |01 which protrudesbeyond the inner face of boss 88 adjacent annular shoulder |02 isretracted so as to permit shoulder |02 to pass -by bar |01 as gearhousing 3| is pulled in an axial direction away from engine casting 84.Bar |01 is bent at its outer end so as to provide a stop |05 forpreventing pin |03v from being completely removed from boss 88.

Referring to Figs. 1 and 10 I have shown my improved engine starting andengine cooling devices. Starter housing ||0 is secured to a secondengine casting by means of bolts ||2. Housing ||0 has an eccentricallylocated sleeve portion I3 extending into the interior of said housing.The inner end of said sleeve ||3 is reduced in diametric dimension so asto provide a bearing for the inner end of starter sleeve I4. Sleeve ||4is provided with internal teeth ||5 which mesh with the external teethon starter pinion ||8. A bushing ||1 is threaded into sleeve ||3 so asto provide a bearing' for the outer end of sleeve |4 and also to providea stopshculder |8 to limit the outward movement of sleeve ||4 relativeto sleeve ||3. A spring washer ||8 is anchored in an annular groove insleeve ||4 and normally abuts against stop shoulder ||8 as a result ofcompression spring |28 which is always under tension. A channel iron issecured to the cuter end of sleeve 4 b'y welding and a handle |2| issecured to the outer end of channel iron |20 forming a hand crankgenerally referred to as |2|A. An elongated slot |22 is located in theouter end of channel iron |20 for receiving the outer end of arm |23.Arm |23 is pivotally mounted within bifurcated boss |24 on housing I |0and a torsion spring |25 normally urges arm |23 about its pivot in acounter-clockwise direction (viewing Fig. 10) so as to rest against thewall of housing ||0.

When starting the engine, crank |2|A is manually pushed inwardly untilteeth l5 engage pinion ||8 secured to engine shaft ||'6A. As soon as theengine starts, spring |28 urges the crank |2|A outwardly into theposition shown in Fig. l0. In order to maintain the gear teeth ||8 outof engagement vwith pinion IIS, arm |23 is swung outwardly (clockwiseviewing Fig. 10) Iand the hook |21 is inserted into slot |22., The Widthof slot |22 is only slightly more than the width of hook |21,consequently the stop shoulders |28 (Fig. 3) o n either side of hook |21engage the outer face of channel iron |20 thereby preventing crank |2 IAfrom moving axially inwardly and in turn preventing teeth ||5 fromengaging with pinion I8.

Embracing sleeve ||3 is a multi-bladed fan |30,

the blades |3| of which extend radially outwardly from hub |32 to theouter supporting ring |33. Said blades are angularly inclined relativeto the axis of hub |32 as indicated by an edge of said blades beingshown in section at |34. Consequently, the air ilows from fan |30 in anaxial directionas indicated by the arrows in Fig. 10. A second fan |36is multi-bladed and its blades |31 extend radially outwardly from engineshaft ISA and also extend axially relative to engine shaft HSA.Consequently fan blades |31 direct the air centrifugally outwardlyasshown by the arrows in Fig. 10. Both fans |30 and |316 are securedtogether through the medium of an annular ring member |38. The fans arespaced from each other so that fan |30 supercharges fan |36 therebyincreasing the amount of air dis charged by fan |36 around the cylinderwalls of the engine, and in turn aording a cooler running temperaturefor the engines. It is to be claim is:

A chainsaw machine comprising a power unit, a chain guiding memberextending therefrom, a transmission housing, a sprocket rotatablysupported y the transmission housing, a cutting chain trained about thesprocket and chain guiding member, va bracket member secured to thetransmission housing, an opening in the bracket through which thesprocket shaft extends, a trough in the bracket member, a carrier havingits underneath surface spanning the trough and riding on the uppersurface of the bracket, a spring resting in the trough and in a groovein the carrier, an adjustment screw extending into the interior of thespring, a shoulder at one end of the bracket against which one end ofthe screw abuts, a nut threaded onto the screw and having a atunderneath surfacespanning the trough, said spring abutting the nut andurging one end of the adjustment screw against the bracket shoulder andan opening in the end of the carrier whereby the adjustment screw may.be

adjusted.

ARTHUR WILLIAM MALL.

